- Turn ignition off. Connect scan tool. If DTC P0101 is only code set, replace MAF sensor. Clear DTC and retest system. If other codes are set, go to next step.
- If DTC P0102 or P0103 are displayed, diagnose and repair those DTCs. DO NOT diagnose DTC P0101. After repair, clear DTC(s) and retest system.
Home/Subaru/Forester/Subaru Forester SF (1997-2000)/Repair manual/Testing & Diagnostics/DTC P0101 (QA_R): MASS AIRFLOW (MAF) SENSOR CIRCUIT RANGE/P…
Contents
Wiring diagrams Section: Testing & Diagnostics- Engine Controls - Tests W/codes: Diagnosis
- Engine Controls - Tests W/codes: Component Locations
- Engine Controls - Tests W/codes: Other
- DTC P0101 (QA_R): MASS AIRFLOW (MAF) SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM
- DTC P0102 (QA_LOW): MASS AIRFLOW (MAF) SENSOR CIRCUIT LOW INPUT
- DTC P0103 (QA_HI): MASS AIRFLOW (MAF) SENSOR CIRCUIT HIGH INPUT
- DTC P0106 (P_R): PRESSURE SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM
- DTC P0107 (P_SLOW): PRESSURE SENSOR CIRCUIT LOW INPUT
- DTC P0108 (P_SHI): PRESSURE SENSOR CIRCUIT HIGH INPUT
- DTC P0116 (TW_LOW): ECT SENSOR CIRCUIT LOW INPUT (LEGACY)
- DTC P0117 (TW_LOW): ECT SENSOR CIRCUIT LOW INPUT (FORESTER & IMPREZA)
- DTC P0117 (TW_HI): ECT SENSOR CIRCUIT HIGH INPUT (LEGACY)
- DTC P0118 (TW_HI): ECT SENSOR CIRCUIT HIGH INPUT (FORESTER & IMPREZA)
- DTC P0121 (TH_R): THROTTLE POSITION (TP) SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM
- DTC P0122 (THV_LOW): TP SENSOR CIRCUIT LOW INPUT
- DTC P0123 (THV_HI): TP SENSOR CIRCUIT LOW INPUT
- DTC P0125 (TW_CL): INSUFFICIENT ENGINE COOLANT TEMPERATURE FOR CLOSED LOOP FUEL CONTROL
- DTC P0130 (FO2_V): FRONT O2S CIRCUIT MALFUNCTION
- DTC P0133 (FO2_R): FRONT O2S CIRCUIT SLOW RESPONSE
- DTC P0135 (FO2H): FRONT O2S HEATER CIRCUIT MALFUNCTION
- DTC P0136 (RO2_V): REAR O2S CIRCUIT MALFUNCTION
- DTC P0139 (RO2_R): REAR O2S CIRCUIT SLOW RESPONSE
- DTC P0141 (RO2_H): REAR O2S HEATER CIRCUIT MALFUNCTION
- DTC P0170 (FUEL): FUEL TRIM MALFUNCTION
- DTC P0181 (TNKT-F): FUEL TEMPERATURE SENSOR A CIRCUIT RANGE/PERFORMANCE
- DTC P0182 (TNKT_LOW): FUEL TEMPERATURE SENSOR A CIRCUIT LOW INPUT
- DTC P0183 (TNKT_HI): FUEL TEMPERATURE SENSOR "A" CIRCUIT HIGH INPUT
- DTC P0261, DTC P0264, DTC P0267 & DTC P0270: FUEL INJECTOR CIRCUIT LOW INPUT
- DTC P0262, P0265, P0268 OR P0271: FUEL INJECTOR CIRCUIT HIGH INPUT
- DTC P0301-DTC P0304: CYLINDER MISFIRE DETECTED
- DTC P0325 (KNOCK): KNOCK SENSOR 1 (KS) CIRCUIT MALFUNCTION
- DTC P0335 (CRANK): CRANKSHAFT POSITION (CKP) SENSOR CIRCUIT MALFUNCTION
- DTC P0336 (CRANK_R): CRANKSHAFT POSITION (CKP) SENSOR RANGE/PERFORMANCE PROBLEM
- DTC P0340 (CAM): CAMSHAFT POSITION (CMP) SENSOR CIRCUIT MALFUNCTION
- DTC P0341 (CAM_R): CAMSHAFT POSITION (CMP) SENSOR RANGE/PERFORMANCE PROBLEM
- DTC P0400 (EGR): EGR FLOW MALFUNCTION
- DTC P0403 (ERGSOL): EGR CIRCUIT LOW INPUT
- DTC P0420 (CAT): CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD
- DTC P0440 (EVAP): EVAP EMISSION CONTROL SYSTEM
- DTC P0441 (CPC_F): EVAP EMISSION CONTROL SYSTEM INCORRECT PURGE FLOW
- DTC P0443 (CPC): EVAP EMISSION CONTROL SYSTEM PURGE CONTROL VALVE CIRCUIT LOW INPUT
- DTC P0446 (VCMSOL_LOW): EVAP EMISSION CONTROL SYSTEM VENT CONTROL LOW INPUT
- DTC P0451 (TNKP_F): EVAP EMISSION CONTROL SYSTEM PRESSURE SENSOR RANGE/PERFORMANCE
- DTC P0452 (TNKP_LOW): EVAP EMISSION CONTROL SYSTEM PRESSURE SENSOR LOW INPUT (FORESTER & 2.5L IMPREZA)
- DTC P0452 (TNKP_LOW): EVAP EMISSION CONTROL SYSTEM PRESSURE SENSOR LOW INPUT (LEGACY & 2.2L IMPREZA)
- DTC P0453 (TNKP_HI): EVAP EMISSION CONTROL SYSTEM PRESSURE SENSOR HIGH INPUT (ALL EXCEPT LEGACY)
- DTC P0453 (TNKP_HI): EVAP EMISSION CONTROL SYSTEM PRESSURE SENSOR HIGH INPUT (LEGACY)
- DTC P0461 (FLVL_R): FUEL LEVEL SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM
- DTC P0463 (FLVL_HI): FUEL LEVEL SENSOR CIRCUIT HIGH INPUT
- DTC P0480 COOLING FAN RELAY NO. 1 LOW INPUT
- DTC P0483 COOLING FAN FUNCTION PROBLEM
- DTC P0500 (VSP): VEHICLE SPEED SENSOR (FORESTER & IMPREZA) (VSS) MALFUNCTION
- DTC P0500 (VSP): VEHICLE SPEED SENSOR (LEGACY) (VSS) MALFUNCTION
- DTC P0505 (ISC): IDLE CONTROL SYSTEM MALFUNCTION
- DTC P0506 (ISC_RLOW): IDLE CONTROL SYSTEM RPM LOWER THAN EXPECTED
- DTC P0507 (ISC_RHI): IDLE CONTROL SYSTEM RPM HIGHER THAN EXPECTED
- DTC P0600: SERIAL COMMUNICATION LINK MALFUNCTION
- DTC P0601 (RAM): INTERNAL CONTROL MODULE MEMORY CHECK SUM ERROR
- DTC P1100 (ST_SWOFF): STARTER SWITCH CIRCUIT LOW INPUT
- DTC P1101 (N_SWOFF): NEUTRAL POSITION SWITCH CIRCUIT MALFUNCTION (A/T)
- DTC P1101 (N_SW): NEUTRAL POSITION SWITCH CIRCUIT MALFUNCTION (M/T)
- DTC P1102 (BR): PRESSURE SOURCES SWITCHING SOLENOID VALVE CIRCUIT LOW INPUT
- DTC P1103 (TRQ): ENGINE TORQUE CONTROL SIGNAL CIRCUIT MALFUNCTION
- DTC P1120 (ST_SWON): STARTER SWITCH CIRCUIT HIGH INPUT
- DTC P1121 (N_SWON): NEUTRAL POSITION SWITCH CIRCUIT LOW INPUT (A/T)
- DTC P1122 (BR_HI): PRESSURE SOURCES SWITCHING SOLENOID VALVE CIRCUIT HIGH INPUT
- DTC P1141 (QA_RHI): MASS AIRFLOW SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM (HIGH INPUT)
- DTC P1142 (TH_RLOW): THROTTLE POSITION SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM (LOW INPUT)
- DTC P1143 (PS_RLOW): PRESSURE SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM (LOW INPUT)
- DTC P1144 (PS_RHI): PRESSURE SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM (HIGH INPUT)
- DTC P1400 (PCVSOL_LO): FUEL TANK PRESSURE CONTROL SOLENOID VALVE CIRCUIT LOW INPUT
- DTC P1420 (PCVSOL_HI): FUEL TANK PRESSURE CONTROL SOLENOID VALVE CIRCUIT HIGH INPUT
- DTC P1421 (EGRSOL_HI): EXHAUST GAS RECIRCULATION CIRCUIT HIGH INPUT
- DTC P1422 (CPC_HI): EVAP EMISSION CONTROL VALVE CIRCUIT HIGH INPUT
- DTC P1423 (VCMSOL_HI): EVAPORATIVE EMISSION CONTROL SYSTEM VENT CONTROL CIRCUIT HIGH INPUT
- DTC P1440 (PCV_FLOW): FUEL TANK PRESSURE CONTROL SYSTEM FUNCTION PROBLEM LOW INPUT
- DTC P1441 (PCV_FHI): FUEL TANK PRESSURE CONTROL SYSTEM FUNCTION PROBLEM HIGH INPUT
- DTC P1442 (FLVL_R2): FUEL LEVEL SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM 2
- DTC P1443 EVAP VENT CONTROL FUNCTION PROBLEM (2.2L IMPREZA & ALL LEGACY MODELS)
- DTC P1507 (ISC_SHI): IDLE CONTROL SYSTEM MALFUNCTION (FAIL-SAFE)
- DTC P1520 (FAN_1HI): RADIATOR FAN RELAY 1 CIRCUIT HIGH INPUT
- DTC P1540 (VSP_S): VEHICLE SPEED SENSOR MALFUNCTION 2
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